Yanovska, E. S., Nikolaeva, O., Kondratenko, O., Vretik, L.  (2019) Sorption properties of saponite clay, in situ modified by poly(4-vinylpyridine-co-styrene), towards Cu(II), Cd(II), Pb(II), Mn(ІІ) and Fe(III) ions.  French-Ukrainian Journal of Chemistry, 7 (2).  с. 153-159.  ISSN 2312-3222